JP2950010B2 - Fuel injection device for electronically controlled diesel engine and method for adjusting fuel injection - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronically controlled diesel engine, and more particularly, to a fuel injection control apparatus for an electronically controlled diesel engine for adjusting the injection timing and amount of fuel injected from a fuel injection pump, and its fuel injection adjustment. It is about the method.

[0002]

2. Description of the Related Art Conventionally, as this kind of technology, for example, JP-A-59-134377 and JP-A-62-2633.
No. 9 is known.

In the former technique, displacement of a disk-shaped pulsar rotated by a drive shaft rotated in association with rotation of a diesel engine, and each projection that passes with the rotation of the pulsar are detected. Thus, the deviation of the fuel injection timing caused by the displacement of the rotation speed sensor (crank angle sensor) that outputs a pulse signal corresponding to the engine rotation speed is corrected by the external correction resistor. That is, an appropriate one of a plurality of external correction resistors having various resistance values is selected and externally connected to the fuel injection pump, and the target control value of the fuel injection timing is corrected.
Thus, an optimal injection timing is obtained.

[0004] In the latter technique, a deviation in fuel injection amount caused by a positional deviation of a pulsar or a rotation speed sensor is corrected by an external correction resistor.
That is, an appropriate one of a plurality of external correction resistors having various resistance values is selected and externally connected to the fuel injection pump, the target control value of the fuel injection amount is corrected, and the optimum injection amount is obtained. Like that.

Therefore, when it is attempted to correct the injection timing and the injection amount to respective optimum values, an external resistance for correcting the injection timing and an external resistance for correcting the injection amount are externally provided to the fuel injection pump. It is possible.

[0006]

However, in recent years,
A fuel injection pump having a high oil feed rate has been used with an increase in the displacement of a diesel engine. Therefore, when a fuel injection pump having a high oil feed rate is used, the range of the injection amount variation becomes large, and the correction thereof has become complicated. That is, if the number of the external resistances for injection quantity correction to be prepared in advance is set to the same value as before without increasing or decreasing, the change in the correction injection quantity per rank (individual) of the external resistance is large. As a result, there is a problem that the correction accuracy is reduced.

In addition, when the change in the correction injection amount per rank in each external resistor is set to be the same as before, a large number of external resistors having different resistance values must be prepared in advance. Therefore, in correcting the injection amount, not only is it not easy to select the external resistance, but also there is a problem that the necessity of stocking a large number of external resistances causes a rise in correction cost.

The present invention has been made in view of the above-described circumstances, and has as its object to provide an electronically controlled diesel engine in which the injection timing and injection amount of fuel injected from a fuel injection pump are corrected by a correction resistor. A fuel injection device for an electronically controlled diesel engine that can easily perform highly accurate correction regardless of an increase in the oil feed rate in the fuel injection pump, and that can suppress a rise in correction cost. An object of the present invention is to provide a fuel injection adjustment method.

[0009]

According to a first aspect of the present invention, as shown in FIG. 1, a camshaft is driven by a drive shaft M6 rotated in conjunction with the rotation of a diesel engine M1. A fuel injection pump M5 for injecting fuel into the diesel engine M1 by pressurizing the fuel in the high-pressure chamber M4 by a plunger M3 reciprocated via M2, and a fuel injection pump M5 provided for the rotation of the drive shaft M6. A disk-shaped pulsar M7 having a plurality of protrusions formed at equal angular intervals on the outer peripheral surface, rotating in conjunction therewith, and provided opposite to the outer peripheral surface of the pulsar M7 and passing with the rotation of the pulsar M7. A rotation speed sensor M8 that outputs a pulse signal corresponding to the engine rotation speed by detecting each protrusion, and a fuel injection pump M
5, an injection timing adjusting means M9 driven to adjust the fuel injection timing from the fuel injection pump M5.
An injection amount adjusting means M10 provided in the fuel injection pump M5 and driven to adjust the fuel injection amount from the fuel injection pump M5, and an injection at each time based on at least a detection result of the rotation speed sensor M8. An injection timing calculating means M11 for calculating a timing command value; an injection timing control means M12 for driving and controlling the injection timing adjusting means M9 based on the injection timing command value calculated by the injection timing calculating means M11; An injection amount calculating means M13 for calculating an injection amount command value at each time based on the detection result of
In a fuel injection control device for an electronically controlled diesel engine comprising an injection amount control means M14 for drivingly controlling an injection amount adjustment means M10 based on an injection amount command value calculated by an injection amount calculation means M13, a pulser M7 and a rotational speed The fuel injection pump M5 is provided externally to the fuel injection pump M5 in order to correct in advance the deviations of the injection timing command value and the injection amount command value caused in the calculation of the injection timing calculation means M11 and the injection quantity calculation means M13 due to the displacement of the sensor M8. , The rotation speed sensor M8 corresponding to the reference projection among the projections of the pulsar M7.
Of the pulse signal output from the fuel injection pump M
5, a first correction resistor M15 having a resistance value for electrically correcting the injection timing command value and the injection amount command value so that the interval from the timing at which fuel is actually injected becomes a predetermined reference value; To further finely adjust the injection amount command value corrected by the first correction resistor M15, the fuel injection pump M5
And a second correction resistor M16 having a resistance value for electrically correcting the injection amount command value calculated by the injection amount calculation means M13.

Further, in the second invention, a plurality of projections provided on the fuel injection pump and rotated at a drive shaft rotated in conjunction with the rotation of the diesel engine and formed on the outer peripheral surface at equal angular intervals are provided. A pulsar having a disk shape, and a rotation speed sensor that outputs a pulse signal corresponding to the engine rotation speed by detecting each projection passing along with the rotation of the pulsar, based on at least a calculation result of the rotation speed sensor. An electronically controlled diesel engine that controls the injection timing and injection amount of fuel to be injected from a fuel injection pump to a diesel engine. In the fuel injection adjustment method in which the deviation is adjusted in advance, first, rotation of the drive shaft in the fuel injection pump is performed. And an injection timing command value and an injection amount command value to be given to the fuel injection pump are respectively set to predetermined values in advance, and then the rotation speed corresponding to each of the reference projections among the pulsar projections is set. The injection timing command value and the injection amount command value are electrically controlled so that the interval between the timing of the pulse signal output from the sensor and the timing at which the fuel is actually injected from the fuel injection pump becomes a predetermined reference value. And a first correction resistor having a resistance value to be corrected
Externally to the fuel injection pump,
With the first correction resistor externally attached to the fuel injection pump, the actual injection amount injected from the fuel injection pump is measured. Then, based on the measurement result of the injection amount, the actual injection amount and the injection amount command value are measured. In order to further fine-tune the deviation between the first and second correction resistors, a second correction resistor having a resistance value for electrically correcting the injection amount command value is selected, and the second correction resistor is externally connected to the fuel injection pump. I have to.

[0011]

According to the structure of the first aspect of the present invention, as shown in FIG. 1, the cam M is linked with the rotation of the diesel engine M1.
The fuel is pressurized in the high-pressure chamber M4 by the reciprocating movement of the plunger M3 through the fuel injection pump M2.
5 to the diesel engine M1. The disk-shaped pulsar M7 provided in the fuel injection pump M5 is
Diesel engine M1 consisting of multiple protrusions on its outer peripheral surface
The same number of cutting teeth as the number of cylinders are formed at equal angular intervals,
It rotates in conjunction with the rotation of the drive shaft M6. The rotation speed sensor M8 detects the passage of the projection of the pulsar M7, outputs a pulse signal, and detects the engine rotation speed.

The injection timing adjusting means M9 provided in the fuel injection pump M5 is driven to adjust the fuel injection timing from the fuel injection pump M5.
The injection amount adjusting means M10 provided in the fuel injection pump 5 is driven to adjust the fuel injection amount from the fuel injection pump M5.
The injection timing calculating means M11 has at least a rotational speed sensor M8.
Is calculated based on the detection result, and the injection timing control means M12 drives and controls the injection timing adjustment means M9 based on the calculation result. Further, the injection amount calculating means M13 calculates the respective injection amount command values based on at least the detection result from the rotation speed sensor M8, and the injection amount control means M14 controls the injection amount adjusting means M10 based on the calculation result. I do.

The first correction resistor M15 has a predetermined reference value that is the interval between the time when the pulse signal of the reference protrusion among the protrusions of the pulser M7 is output and the time when the fuel is actually injected. As described above, the resistance value for electrically correcting the calculation of the injection timing command value in the injection timing calculation means M11 is provided. When the first correction resistor M15 is externally connected to the fuel injection pump M5, the injection timing command value calculated by the injection timing calculation means M11 due to the displacement of the pulser M7 and the rotation speed sensor M8. Is corrected in advance. Here, since the difference between the injection timing command value and the difference between the injection amount command values is often due to the same kind of factors, the difference between the injection timing command values is corrected in advance and simultaneously calculated by the injection amount calculating means M13. The deviation of the injection amount command value is also corrected in advance. That is, one first correction resistor M
By using No. 15, the deviation between the injection timing command value and the injection amount command value is corrected.

The second correction resistor M16 electrically corrects the calculation of the fuel injection amount command value by the injection amount calculation means M13 when the first correction resistor M15 is externally connected to the fuel injection pump M5. Resistance value. And
By externally attaching the second correction resistor M16 to the fuel injection pump M5, the injection amount command value corrected by the first correction resistor M15 is further finely adjusted.

Therefore, the deviation of the injection amount command value is roughly corrected in advance by the first correction resistor M15 and then finely corrected by the second correction resistor M16. Therefore, the correction target range of the second correction resistor M16 is reduced. Also, the second to be prepared in advance
When the number of the correction resistors M16 is constant, it is possible to reduce the change in the injection amount per rank of the second correction resistor M16, that is, the injection amount correction width.

In the second invention, the number of rotations of a fuel injection pump for injecting fuel into a diesel engine is determined by:
An injection timing command value to the injection timing adjustment means driven to adjust the injection timing from the fuel injection pump and an injection quantity command value driven to adjust the injection quantity from the fuel injection pump are preset. Is done. Then, the first time is set so that the interval between the time when the pulse signal of the reference protrusion among the protrusions of the pulsar is output by the rotation speed sensor and the time when the fuel is actually injected becomes a predetermined reference value. A correction resistor is selected. The injection timing command value to the injection timing adjusting means is electrically corrected by the selected first correction resistor,
The shift of the fuel injection timing from the fuel injection pump to the diesel engine caused by the position shift of the pulsar or the rotation speed sensor is corrected. In addition, since the difference between the injection timing command value and the difference between the injection amount command values is often due to the same type of factor, the difference between the injection timing command values is corrected in advance, and at the same time, the difference between the injection amount command values is also determined in advance. Will be corrected. That is, the deviation between the injection timing command value and the injection amount command value is corrected by using one first correction resistor.

Next, the actual injection amount injected from the fuel injection pump is measured with the first correction resistor externally attached to the fuel injection pump, and based on the measurement result, the injection amount to the injection amount adjusting means is measured. A second correction resistor having a resistance value for electrically correcting the command value is selected, and the second correction resistor is also externally connected to the fuel injection pump. Then, the injection amount command value corrected by the first correction resistor is further finely adjusted, and the shift of the injection amount caused by the position shift of the pulsar or the rotation speed sensor is accurately corrected. At this time, since the injection amount is roughly corrected by the first correction resistor, the correction width of the second correction resistor is small. Therefore, the second correction resistor is easily selected.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which a fuel injection control device and a fuel injection adjustment method for an electronically controlled diesel engine according to the present invention are embodied in an automobile will be described in detail with reference to the drawings.

FIG. 2 is a schematic structural view showing a fuel injection control device for a supercharged diesel engine in this embodiment, and FIG. 3 is a sectional view showing the distribution type fuel injection pump 1. The fuel injection pump 1 includes a drive pulley 3 which is drivingly connected to a crankshaft 40 of the diesel engine 2 via a belt or the like. The fuel injection pump 1 is driven by the rotation of the drive pulley 3, and the fuel is injected under pressure to each fuel injection nozzle 4 provided for each cylinder (four cylinders in this case) of the diesel engine 2 to perform fuel injection. .

In the fuel injection pump 1, the drive pulley 3 is attached to a tip of a drive shaft 5.
In the middle of the drive shaft 5, there is provided a fuel feed pump (developed at 90 degrees in this figure) 6 composed of a vane type pump. Further, a disk-shaped pulser 7 is attached to the base end side of the drive shaft 5. The outer surface of the pulsar 7 has a diesel engine 2
In other words, in this case, four incisors are formed at equal angular intervals, and in this case, 14 projections (56 in total) are formed at equal angular intervals between each incisor. ing. The base end of the drive shaft 5 is connected to a cam plate 8 as a cam via a coupling (not shown).

A roller ring 9 is provided between the pulsar 7 and the cam plate 8, and a plurality of cam rollers 10 facing the cam face 8a of the cam plate 8 are mounted along the circumference of the roller ring 9. I have. Cam face 8
a is provided as many as the number of cylinders of the diesel engine 2. The cam plate 8 is always urged and engaged with the cam roller 10 by the spring 11.

A base end of a fuel pressurizing plunger 12 is attached to the cam plate 8 so as to be integrally rotatable. The cam plate 8 and the plunger 12 are rotated in conjunction with the rotation of the drive shaft 5. That is, the rotational force of the drive shaft 5 is transmitted to the cam plate 8 via a coupling (not shown), so that the cam plate 8 rotates and engages with the cam roller 10 to rotate in the left-right direction by the same number as the number of cylinders. Is reciprocated. Further, the plunger 12 is driven to reciprocate in the same direction while rotating with the reciprocation. That is, the plunger 12 is moved forward (lift) while the cam face 8a of the cam plate 8 rides on the cam roller 10 of the roller ring 9, and conversely, the plunger 1 is moved while the cam face 8a rides down the cam roller 10.
2 is reactivated.

The plunger 12 is inserted into a cylinder 14 formed in the pump housing 13, and a high pressure chamber 15 is formed between the tip of the plunger 12 and the bottom of the cylinder 14.
It has become. Also, on the outer periphery of the tip side of the plunger 12,
The same number of intake grooves 16 and distribution ports 17 as the number of cylinders of the diesel engine 2 are formed. A distribution passage 18 and a suction port 19 are formed in the pump housing 13 corresponding to the suction groove 16 and the distribution port 17.

Then, when the drive shaft 5 is rotated and the fuel feed pump 6 is driven, fuel is supplied from a fuel tank (not shown) into the fuel chamber 21 through the fuel supply port 20. Also, during the suction stroke in which the plunger 12 is moved back and the high-pressure chamber 15 is depressurized, the suction groove 1
The fuel is introduced from the fuel chamber 21 to the high-pressure chamber 15 when one of the ports 6 communicates with the suction port 19. On the other hand, during the compression stroke in which the plunger 12 is moved forward and the high-pressure chamber 15 is pressurized, fuel is pressure-fed from the distribution passage 18 to the fuel injection nozzle 4 of each cylinder and injected.

The pump housing 13 is provided with a spill passage 22 for fuel spill that connects the high-pressure chamber 15 and the fuel chamber 21. In the middle of the spill passage 22, there is provided an electromagnetic spill valve 23 as an injection amount adjusting means for adjusting the fuel spill from the high pressure chamber 15.
This electromagnetic spill valve 23 is a normally open type valve, and a coil 24
Is in a non-energized (off) state, the valve body 25 is opened, and the fuel in the high-pressure chamber 15 is spilled to the fuel chamber 21. When the coil 24 is energized (turned on), the valve body 25 is closed, and the spill of fuel from the high-pressure chamber 15 to the fuel chamber 21 is stopped.

Therefore, by controlling the energization time of the electromagnetic spill valve 23, the valve 23 is controlled to close and open, and the spill amount of fuel from the high-pressure chamber 15 to the fuel chamber 21 is adjusted. Then, by opening the electromagnetic spill valve 23 during the compression stroke of the plunger 12, the fuel in the high-pressure chamber 15 is reduced in pressure, and the fuel injection from the fuel injection nozzle 4 is stopped. That is, even when the plunger 12 moves forward, the fuel pressure in the high-pressure chamber 15 does not increase while the electromagnetic spill valve 23 is open, and the fuel injection from the fuel injection nozzle 4 is not performed. Further, during the forward movement of the plunger 12, by controlling the timing of closing and opening the electromagnetic spill valve 23, the amount of fuel injected from the fuel injection nozzle 4 is controlled.

At the lower side of the pump housing 13, there is provided a timer device (developed at 90 degrees in this figure) 26 constituting the injection timing adjusting means. The timer device 26 changes the position of the roller ring 9 with respect to the rotation direction of the drive shaft 5 so that the cam face 8
This is for changing the timing at which a engages with the cam roller 10, that is, the reciprocating drive timing of the cam plate 8 and the plunger 12.

The timer device 26 is driven by hydraulic pressure, and includes a timer housing 27, a timer piston 28 fitted in the housing 27, and a timer chamber 29 on one side of the timer housing 27. A timer spring 31 for urging the piston 28 toward the other pressurizing chamber 30 is provided. The timer piston 28 is connected to the roller ring 9 via a slide pin 32.

In the pressurizing chamber 30 of the timer housing 27,
The fuel pressurized by the fuel feed pump 6 is introduced. The position of the timer piston 28 is determined by the balance between the fuel pressure and the urging force of the timer spring 31. Further, by determining the position of the timer piston 28, the position of the roller ring 9 is determined, and the reciprocating timing of the plunger 12 via the cam plate 8 is determined.

In order to adjust the fuel pressure acting as the hydraulic pressure of the timer device 26, the timer device 26 is provided with a timer control valve (TCV) 33 which also constitutes injection timing adjusting means. That is, the pressurizing chamber 30 and the low-pressure chamber 29 of the timer housing 27 communicate with each other through the communication path 34, and the TCV 33 is provided in the communication path 34. The TCV 33 is an electromagnetic valve whose opening and closing are controlled by a duty-controlled energization signal, and the fuel pressure in the pressurizing chamber 30 is adjusted by controlling the opening and closing of the TCV 33. Then, by adjusting the fuel pressure, the lift timing of the plunger 12 is controlled, and the fuel injection timing from each fuel injection nozzle 4 is controlled.

On the upper part of the roller ring 9, a rotation speed sensor 35 composed of an electromagnetic pickup coil is mounted so as to face the outer peripheral surface of the pulser 7. This rotation speed sensor 35
Detects the passage of the projections of the pulsar 7 when they cross, and outputs an engine rotation pulse (NE pulse) signal corresponding to the engine rotation speed NE. Further, since the rotation speed sensor 35 is integrated with the roller ring 9, the rotation speed sensor 35 outputs a reference timing signal to the plunger lift at a constant timing regardless of the control operation of the timer device 26.

Next, the diesel engine 2 will be described. This diesel engine 2 has a cylinder bore 4
1, a main combustion chamber 44 corresponding to each cylinder is formed by the piston 42 and the cylinder head 43. Further, the sub combustion chamber 45 communicating with each of the main combustion chambers 44 is provided.
Are provided for each cylinder. Each sub-combustion chamber 45 is supplied with fuel injected from each fuel injection nozzle 4. Further, a well-known glow plug 46 as a start-up assist device is attached to each sub-combustion chamber 45.

The diesel engine 2 has an intake passage 47
And an exhaust passage 48 are provided, and the intake passage 4
7 is provided with a compressor 50 of a turbocharger 49 constituting a supercharger, and an exhaust passage 48 is provided with a turbine 51 of the turbocharger 49. The exhaust passage 48 is provided with a waste gate valve 52 for adjusting the supercharging pressure PiM. As is well known, the turbocharger 49 uses the energy of the exhaust gas to rotate the turbine 51, and rotates the compressor 50 on the same axis to increase the pressure of the intake air. By this action, high-density air is sent into the main combustion chamber 44 to burn a large amount of fuel, thereby increasing the output of the diesel engine 2.

The diesel engine 2 is provided with an exhaust gas recirculation passage (EGR passage) 54 for recirculating a part of the exhaust gas in the exhaust passage 48 to the intake port 53 of the intake passage 47. And that E
An exhaust gas recirculation valve (EGR valve) for adjusting the amount of exhaust gas recirculation is provided in the GR passage 54.
55 are provided. The opening and closing of the EGR valve 55 is controlled by the control of a vacuum switching valve (VSV) 56.

Further, in the middle of the intake passage 47, a throttle valve 58 which is opened and closed in conjunction with the depression amount of an accelerator pedal 57 is provided. A bypass passage 59 is provided in parallel with the throttle valve 58, and a bypass throttle valve 60 is provided in the bypass passage 59.
The opening and closing of the bypass throttle valve 60 is controlled by an actuator 63 having a two-stage diaphragm chamber driven by control of two VSVs 61 and 62. The opening and closing of the bypass throttle valve 60 is controlled in accordance with various operation states. For example, it is controlled to a half-open state during idle operation to reduce noise and vibration, to a fully opened state during normal operation, and to a fully closed state during smooth operation to stop smoothly.

The electromagnetic spill valve 2 provided on the fuel injection pump 1 and the diesel engine 2 as described above
3, TCV33, glow plug 46 and each VSV56,
61 and 62 are injection timing calculation means, injection timing control means,
The ECU 71 is electrically connected to an electronic control unit (hereinafter simply referred to as “ECU”) 71 that constitutes the injection amount calculation unit and the injection amount control unit, and the ECU 71 controls the drive timing thereof.

As sensors for detecting the operating state of the diesel engine 2, the following various sensors are provided in addition to the rotation speed sensor 35. That is, in the vicinity of the air cleaner 64 provided at the inlet of the intake passage 47, an intake air temperature sensor 72 for detecting the intake air temperature is provided. Further, an accelerator sensor 73 for detecting an accelerator opening ACCP corresponding to the load of the diesel engine 2 from the open / close position of the throttle valve 58 is provided. In the vicinity of the intake port 53, there is provided an intake pressure sensor 74 for detecting the intake air pressure after being supercharged by the turbocharger 49, that is, the supercharging pressure PiM. Further, a water temperature sensor 75 for detecting a cooling water temperature of the diesel engine 2 is provided. Further, a crank angle sensor 76 for detecting a rotation reference position of the crankshaft 40, for example, a rotation position of the crankshaft 40 with respect to a top dead center of a specific cylinder is provided. Further, a transmission (not shown) is provided with a vehicle speed sensor 77 for detecting a vehicle speed by turning on / off a reed switch 77b by a magnet 77a rotated by rotation of the gear.

Further, the fuel injection pump 1 is provided with an injection timing adjustment resistor 78 as a first correction resistor and an injection amount adjustment resistor 79 as a second correction resistor in advance before shipment of the fuel injection pump 1. Have been. Injection timing adjustment resistance 7
8 has a resistance value VRT, and the injection amount adjustment resistor 79 has a resistance value VRP.

The ECU 71 is connected to the above-mentioned sensors 72 to 77 and the rotation speed sensor 35, and is also connected to the injection timing adjustment resistor 78 and the injection amount adjustment resistor 79. In addition, the ECU 71 controls the sensors 35, 72
, The TCV 33, the glow plug 46, the VSV 56,
61, 62, etc. are suitably controlled.

Next, the configuration of the ECU 71 will be described with reference to the block diagram of FIG. The ECU 71 has a central processing unit (CPU) 81, a read-only memory (RO) storing a predetermined control program, a map, and the like in advance.
M) 82, a random access memory (RAM) 83 for temporarily storing the operation results and the like of the CPU 81, a backup RAM 84 for storing previously stored data, and the like, and a bus 87 for connecting these components to the input port 85 and the output port 86.
Are configured as logical operation circuits connected with each other.

The input port 85 is provided with the above-described intake air temperature sensor 72, accelerator sensor 73, intake pressure sensor 74, and water temperature sensor 75, and buffers 88, 89, 90, 91, respectively.
They are connected via a multiplexer 93 and an A / D converter 94. Similarly, an injection timing adjustment resistor 78 and an injection amount adjustment resistor 79 are connected to the input port 85 via a multiplexer 93 and an A / D converter 94. Further, the input port 85 also has the above-described rotation speed sensor 35, crank angle sensor 76, and vehicle speed sensor 77,
It is connected via a waveform shaping circuit 95. And C
The PU 81 reads, as an input value, a detection signal of each of the sensors 35, 72 to 77, etc., which is input through the input port 85. The output ports 86 are connected to the respective driving circuits 96, 97, 9
8, 99, 100, 101, 102, the electromagnetic spill valve 23, the TCV 33, the glow plug 46 and the VSV 5
6, 61, 62, 69, etc. are connected.

Then, the CPU 81 controls each of the sensors 35 and 72.
Based on the input value read from ~ 77, the electromagnetic spill valve 2
3, TCV33, glow plug 46 and VSV56,6
1, 62, 69, etc. are suitably controlled.

In particular, the opening / closing timing of the electromagnetic spill valve 23 controlled by the CPU 81, ie, the injection amount command value Q
FIN is electrically corrected by the injection timing adjusting resistor 78. The opening / closing timing of the TCV 33 controlled by the CPU 81, that is, the control duty ratio DUTY of the TCV 33 is electrically corrected by the injection amount adjustment resistor 79.

Next, before shipment of the fuel injection pump 1 of this embodiment, in order to adjust the fuel injection amount and the fuel injection timing, an injection timing adjustment resistor 78 and an injection amount adjustment resistor 79 are adopted. A series of work procedures when mounting the pump 1 will be described with reference to FIG. FIG. 5 is a flowchart showing a flow of work performed by an operator in an adjustment stage before shipment. The injection timing adjustment resistor 7
It is assumed that several kinds of 8 and the injection amount adjusting resistor 79 are prepared in advance.

In this adjustment step, first, at step 001, the pump speed NP of the fuel injection pump 1 (equal to the engine speed NE, that is, the speed of the drive shaft 5), the injection amount command values QFIN and TC
The control duty ratio DUTY of V33 is set to a predetermined value. Here, the pump rotation speed NP and the injection amount command value QFIN are set to standard predetermined values during idling rotation, and the control duty ratio DUTY is set to 100% at which the timer becomes the most retarded angle.

In the next step 002, based on the value detected by the rotation speed sensor 35, as shown in FIG.
Of the NE pulses up to "$ 13"
The interval d between the pulse “# 2” and the injection start timing in the injection waveform is measured.

In the following step 003, a resistance value VRT is selected based on the interval d measured in step 002 so that the interval d becomes a target interval, and an injection timing adjusting resistor 78 having the resistance value VRT is previously determined. It is selected from a plurality of injection timing adjustment resistors. Then, the injection timing adjusting resistor 78 is externally connected to the fuel injection pump 1. The injection timing adjustment resistor 78 corrects a variation in the fuel injection timing and the injection amount due to the displacement of the pulser 7 and the rotation speed sensor 35.

Here, an injection timing correction angle QV obtained by converting a resistance value VRT for correcting the injection timing into a crank angle.
FIG. 7 is a graph showing the experimentally confirmed correlation between the RT and the injection amount correction angle QVRP obtained by converting the resistance value VRP for correcting the injection amount into the crank angle. As is clear from this graph, there is a very clear correlation between the injection timing correction angle QVRT and the injection amount correction angle QVRP. The reason is that the difference between the fuel injection timing and the injection amount is mainly due to the same kind of factor. Therefore, as shown in FIG. 8, by correcting the deviation of the fuel injection timing by the resistance value VRT, the deviation of the fuel injection amount is corrected with a certain width.

In the next step 004, with the injection timing adjusting resistor 78 externally attached to the fuel injection pump 1,
The fuel injection amount from the fuel injection pump 1 is actually measured. At this time, since the deviation of the fuel injection amount has already been corrected with a certain width in step 003, the degree of the deviation of the fuel injection amount is very small.

Finally, in step 005, a resistance value VRP is selected such that the difference between the injection amount measured in step 004 and the target injection amount becomes substantially zero, and an injection amount adjusting resistor 79 having the resistance value VRP is selected. It is selected from a plurality of injection amount adjustment resistors prepared in advance. Then, the injection amount adjusting resistor 79 is externally attached to the fuel injection pump 1.
Thereby, the variation in the injection amount is corrected. At this time, as described above, since the degree of deviation of the fuel injection amount is very small, the fine adjustment range of the resistance value VRP of the injection amount adjustment resistor 79 to be selected is, as shown in FIG. In comparison, it is extremely narrow. Therefore, when the number of injection amount adjustment resistors prepared in advance is the same, the adjustment accuracy (resolution) per rank can be increased. If the resolution per rank is the same as the conventional one, the number of injection amount adjustment resistors prepared in advance can be reduced. Therefore, even when the oil supply rate of the fuel injection pump 1 is increased, it is not necessary to increase the number of the injection amount adjustment resistors, and the fuel injection pump 1 can be easily adopted.

As described above, in the adjustment stage before shipment of the fuel injection pump 1, the injection timing adjustment resistor 78 and the injection amount adjustment resistor 79 are attached to the fuel injection pump 1, respectively. Then, the variation is adjusted so that the injection timing and the injection amount coincide with a predetermined value.

Next, with the injection timing adjustment resistor 78 and the injection amount adjustment resistor 79 attached to the fuel injection pump 1, the ECU
The processing operation of the fuel injection timing control and the fuel injection amount control executed by 71 will be described with reference to FIGS.

First, the flowchart shown in FIG.
The processing routine for controlling the fuel injection timing among the processing executed by the processing 71 is executed by a periodic interruption every predetermined time.

When the process proceeds to this routine, first, at step 101, the actual crank angle timing ACTCA corresponding to the actual injection timing is read. Here, the actual crank angle timing ACTCA is determined in a separate processing routine by a reference crank angle signal (TDC
Signal) and the NE pulse from the rotation speed sensor 35. The actual crank angle timing ACTCA includes an injection timing correction angle QVRT based on the resistance value VRT of the injection timing adjustment resistor 78.

Next, at step 102, a target crank angle timing TRGCA corresponding to a target injection timing calculated by a separate processing routine is read. In step 103, the deviation Δ between the currently read target crank angle timing TRGCA and the actual crank angle timing ACTCA is calculated.
Calculate T.

Subsequently, in step 104, the actual crank angle timing ACTCA is calculated based on the deviation ΔT calculated this time.
Is calculated such that the control duty ratio DUTY becomes equal to the target crank angle timing TRGCA. At this time, the actual crank angle timing ACTCA is electrically corrected by the resistance value VRT of the injection timing adjustment resistor 78. Accordingly, the calculation of the pulsar 7 and the control duty ratio DUTY is performed in a state where the shift of the fuel injection timing caused by the shift of the rotation speed sensor 35 and the like is corrected.

At step 105, TCV3 is calculated based on the calculated control duty ratio DUTY.
3 is duty-controlled, and the subsequent processing is temporarily terminated.
Next, the flowchart shown in FIG. 10 is a processing routine for controlling the fuel injection amount among the processing executed by the ECU 71, and is executed by a periodic interruption every predetermined time.

When the process proceeds to this routine, first, in step 201, the engine speed NE, the accelerator opening ACCP and the supercharging pressure PiM based on the detection of the rotation speed sensor 35, the accelerator sensor 73 and the intake pressure sensor 74 are read. .

In the following step 202, the injection amount command value QFIN is calculated based on the currently read engine speed NE, accelerator opening ACCP, supercharging pressure PiM, and the like.

In step 203, the target spill opening angle AN is calculated by adding the injection timing correction angle QVRT and the injection amount correction angle QVRP to the injection amount command value QFIN.
Set as GSPV. That is, the target spill opening angle ANGSPV is a value obtained by correcting the injection amount command value QFIN calculated according to the operating state by using the injection timing correction angle QVRT and the injection amount correction angle QVRP. Here, the injection timing correction angle QVRT corresponds to the resistance value VRT of the injection timing adjustment resistor 78, and corrects a certain degree of variation in the fuel injection amount.
Further, the injection amount correction angle QVRP is equivalent to the resistance value VRP of the injection amount adjustment resistor 79, and further finely corrects the variation of the injection amount with some correction.

In step 204, the opening timing of the electromagnetic spill valve 23 is controlled based on the target spill opening angle ANGSPV calculated this time. That is, the drive of the electromagnetic spill valve 23 is controlled by the target spill opening angle ANGSPV corrected by the injection timing correction angle QVRT and the injection amount correction angle QVRP.

Therefore, even if the pulsar 7 and the rotational speed sensor 35 are misaligned, the spill opening angle ANGSPV
Since the state is corrected to a proper state without any deviation, an accurate fuel injection amount can be obtained. As explained above,
According to this embodiment, in the adjustment stage of the fuel injection pump 1, first, the injection timing adjustment resistor 78 is adopted, and the resistance value VRP for correcting the fuel injection amount in a state where it is externally attached to the fuel injection pump 1. Is adopted, and it is externally connected to the fuel injection pump 1. Therefore, when the resistance value VRP is selected, the injection amount adjustment resistor 78 has already performed some injection amount correction, and the adjustment range of the selected resistance value can be reduced. Therefore, when the number of the injection amount adjustment resistors 79 to be prepared in advance is the same as that of the related art, the change in the injection amount per rank can be reduced, and more accurate correction can be performed. . On the other hand, when the fuel injection pump 1 having a high oil feed rate is used, 1
When the change in the injection amount per rank is the same as the conventional one, the number of the injection amount correction resistors prepared in advance can be reduced, so that the selection is easy, the adjustment is easy, and the cost is reduced. be able to.

Further, in this embodiment, when actually controlling the fuel injection pump 1, based on the actual crank angle timing ACTCA added by the injection timing correction angle QVRT based on the resistance value VRT of the injection timing adjustment resistor 78. , TC
The control duty ratio DUTY of V33 is calculated. Therefore, even if the pulsar 7 and the rotational speed sensor 35 are misaligned, the misalignment of the injection timing due to the misalignment can be accurately corrected.

Further, in this embodiment, the injection amount command value Q
The value obtained by adding the injection timing correction angle QVRT and the injection amount correction angle QVRP to FIN is used as the target spill opening angle ANGSPV.
The opening angle of the electromagnetic spill valve 23 is controlled based on the target spill opening angle ANGSPV. Therefore, even if the pulsar 7 or the rotational speed sensor 35 is displaced, the displacement of the injection amount due to the displacement can be accurately corrected. That is, by using two resistors, the injection timing adjustment resistor 78 and the injection amount adjustment resistor 79,
The deviation of the injection timing and the injection amount can be corrected.

It should be noted that the present invention is not limited to the above-described embodiment, and may be carried out as follows by appropriately changing a part of the configuration without departing from the spirit of the invention. (1) In the above embodiment, the predetermined values set in the adjustment stage, that is, the pump rotation speed NP and the injection amount command value QFI
N is a standard value at the time of idling rotation, and the control duty ratio DUTY is 100% at which the timer becomes the most retarded angle.
However, each value is not limited to the above-described embodiment, and may be another value.

(2) In the above embodiment, the diesel engine 2 provided with the turbocharger 49 as the supercharger is embodied. However, the diesel engine provided with the supercharger as the supercharger or the supercharger is provided. Not embodied in diesel engines.

[0067]

As described above in detail, according to the fuel injection device for an electronically controlled diesel engine and the method for adjusting the fuel injection of the electronically controlled diesel engine of the present invention, the injection timing and the injection amount of the fuel injected from the fuel injection pump are corrected by the correction resistor. In the electronically controlled diesel engine to be corrected in the above, the fuel injection timing and the fuel injection amount are corrected by the first correction resistor in order to previously correct the difference between the injection timing command value and the injection amount command value,
In order to further finely adjust the injection amount command value corrected in a state where the first correction resistance is externally attached to the fuel injection pump, the fuel injection amount is corrected by the second correction resistance.
Highly accurate correction can be easily performed irrespective of an increase in the oil feed rate in the fuel injection pump, and an excellent effect of suppressing an increase in correction cost can be achieved.

[Brief description of the drawings]

FIG. 1 is a conceptual configuration diagram illustrating a basic conceptual configuration of the present invention.

FIG. 2 is a schematic configuration diagram showing a fuel injection control device for an electronically controlled diesel engine according to an embodiment of the present invention.

FIG. 3 is a cross-sectional view illustrating a distribution type fuel injection pump according to one embodiment.

FIG. 4 is a block diagram showing a configuration of an ECU and the like in one embodiment.

FIG. 5 is a flowchart showing a flow of an adjustment operation performed by an operator in an adjustment stage of the fuel injection pump in one embodiment.

FIG. 6 is a time chart illustrating a correspondence relationship between an engine rotation pulse and a fuel injection waveform in one embodiment.

FIG. 7 is a graph illustrating a relationship between an injection amount correction angle and an injection timing correction angle in one embodiment.

FIG. 8 is a conceptual diagram illustrating a relationship between a resistance value of an injection amount correction resistor and a resistance value of an injection amount correction resistor in one embodiment.

FIG. 9 is a flowchart illustrating a processing routine of fuel injection timing control executed by an ECU in one embodiment.

FIG. 10 is a flowchart illustrating a processing routine of fuel injection amount control executed by an ECU in one embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Fuel injection pump, 2 ... Diesel engine, 5 ... Drive shaft, 7 ... Pulser, 8 ... Cam plate as a cam, 12 ... Plunger, 15 ... High pressure chamber, 23 ... Electromagnetic spill valve as an injection amount adjusting means, 26 ... Timer device constituting injection timing adjusting means, 33 TCV constituting injection timing adjusting means, 35 rotation speed sensor, 71 injection timing calculating means, injection timing control means, injection quantity calculating means and injection quantity controlling means. ECUs to be configured, 78: injection timing adjustment resistance as a first correction resistance, 79: injection amount adjustment resistance as a second correction resistance.

Claims (2)

(57) [Claims] 1. A fuel injection pump for injecting fuel into a diesel engine by pressurizing the fuel in a high-pressure chamber by a plunger reciprocated via a cam by a drive shaft rotated in conjunction with the rotation of the diesel engine. A disk-shaped pulsar provided on the fuel injection pump, rotating in conjunction with the rotation of the drive shaft, and having a plurality of projections formed at equal angular intervals on an outer peripheral surface; and an outer peripheral surface of the pulsar. A rotation speed sensor that is provided to face each other and outputs a pulse signal corresponding to an engine rotation speed by detecting each projection that passes along with the rotation of the pulsar; and a fuel injection pump that is provided to the fuel injection pump. An injection timing adjusting means driven to adjust the fuel injection timing from the fuel injection pump; Injection amount adjusting means driven to adjust the fuel injection amount from the fuel injection timing calculating means for calculating an injection timing command value at each time based on at least a detection result of the rotation speed sensor; and Injection timing control means for driving and controlling the injection timing adjusting means based on the injection timing command value calculated by the means; and an injection quantity for calculating an injection quantity command value at each time based on at least a detection result of the rotation speed sensor. A fuel injection control device for an electronically controlled diesel engine, comprising: a calculation unit; and an injection amount control unit that drives and controls the injection amount adjustment unit based on the injection amount command value calculated by the injection amount calculation unit. And the injection timing respectively generated in the calculation of the injection timing calculating means and the injection amount calculating means due to the displacement of the rotation speed sensor. In order to correct in advance the difference between the command value and the injection amount command value, a pulse signal output from the rotation speed sensor, which is externally attached to the fuel injection pump and is output from the rotation speed sensor corresponding to a reference projection among the projections of the pulsar. And a resistance value for electrically correcting the injection timing command value and the injection amount command value so that the interval between the timing and the timing at which the fuel is actually injected from the fuel injection pump becomes a predetermined reference value. And an injection amount command value which is externally attached to the fuel injection pump and is calculated by the injection amount calculation means in order to further finely adjust the injection amount command value corrected by the first correction resistor. And a second correction resistor having a resistance value that electrically corrects the electric resistance of the fuel injection control device of the electronically controlled diesel engine. 2. A disk-shaped pulsar provided on a fuel injection pump and rotated by a drive shaft rotated in conjunction with rotation of a diesel engine and having a plurality of projections formed at equal angular intervals on an outer peripheral surface. A rotation sensor that outputs a pulse signal corresponding to an engine rotation speed by detecting each projection that passes along with the rotation of the pulsar, and the fuel injection is performed based on at least a calculation result of the rotation speed sensor. An electronically controlled diesel engine for controlling an injection timing and an injection amount of fuel to be injected from a pump to the diesel engine, wherein the injection timing and the injection amount generated due to a displacement of the pulsar and the rotation speed sensor and the like. In a fuel injection adjustment method in which a shift is adjusted in advance, first, the driveshaft in the fuel injection pump is adjusted. And the injection timing command value and the injection amount command value to be given to the fuel injection pump are previously set to predetermined values, respectively. The injection timing command value is set so that the interval between the timing of the pulse signal output from the rotation speed sensor and the timing at which fuel is actually injected from the fuel injection pump becomes a predetermined reference value. And selecting a first correction resistor having a resistance value for electrically correcting the injection amount command value, and externally connecting the first correction resistor to the fuel injection pump. Measure the actual injection amount injected from the fuel injection pump in a state where the resistance is externally attached to the fuel injection pump, and then, based on the measurement result of the injection amount, determine the actual injection amount and the injection amount command value. Further fine-tuning the gap between Electronic control, wherein a second correction resistor having a resistance value for electrically correcting the injection amount command value is selected, and the second correction resistor is externally connected to the fuel injection pump. How to adjust fuel injection for diesel engines.